<!DOCTYPE html>

<style>
  #clip {
    position: absolute;
    overflow: hidden;
    width: 300px;
    height: 300px;
  }

  #transform {
    transform: scale3d(2, 2, 1);
    background-color: blue;
    width: 200px;
    height: 200px;
  }

  #fixed {
    will-change: transform;
    position: fixed;
    top: 50px;
    left: 50px;
    width: 100px;
    height: 100px;
    background-color: green;
  }
</style>

<div id='clip'>
  <div id='transform'>
    <div id='fixed'></div>
  </div>
</div>
